Doctor of Philosophy (PhD)


Biological Sciences

Document Type



The interactions between a host and its infectious pathogen are influenced by multiple environmental factors such as the temperature. Ongoing anthropogenic mediated changes such as global climate change cause shifts in the average temperature, which changes global atmospheric and oceanic circulation patterns leading to overall abiotic shifts. These changes cause the locations of suitable habitats to shift and the outcomes of the host-pathogen interactions to vary. To understand the future of disease dynamics and how disease systems will respond to global changes, the current and altered state of host-pathogen interactions must be examined. This dissertation examines the current understanding of disease dynamics through existing human diseases systems spanning multiple pathogen species across the globe. Particularly, emphasis is given to exploring the differences in R0, the reproductive rate of spread of a disease. and how this metric correlates with other disease metrics associated with disease transmission such as the recovery and mortality rate. Additionally, comparisons were made between the pathogen types (bacteria and virus) as well as between the hemispheres (Northern and Southern). Attempting to identify the current trends in differences between human diseases. Next, the coevolutionary dynamics of host-pathogens were examined under the influence of temperature to determine potential outcomes of disease transmission under climate regime shifts. The fall armyworm, Spodoptera frugiperda, and its species specific baculovirus were used to examine how the interaction would change between a low, optimal, and high temperature treatment, derived from the host’s thermal performance curve, across multiple generations. Attempting to determine how the virulence of the virus impacts the host. Finally, the disease dynamics outside of the native range of the host were compared to the non-native range of a widely distributed plant species, Plantago lanceolata, which becomes infected with a number of different pathogens. A long-term dataset was used to examine potential impacts of disease given the species distribution. In sum, this dissertation looks at how disease systems will be affected due to the ongoing shifts of abiotic factors arising from global climate.



Committee Chair

Bret Elderd

Available for download on Sunday, May 09, 2027